Life-saving sprinkler systems have one essential element and that, of course, is water. But how is water delivered when fire breaks out? Where does it come from?
Sources of water for sprinkler systems
Although water can be directly delivered from a mains supply, this is not considered the most reliable source – even with a booster pump. Because sprinkler systems play a vital role in life safety and asset protection, water supply cannot be left to chance. That is why most sprinkler systems depend on water that is stored in an on-site tank specifically designed and designated for fire-fighting purposes.
When a fire is detected, an automatic sprinkler system will deliver water from a full-holding, on-site tank to stop it from spreading and to keep routes of escape clear. Pumps, less commonly just a single pump, are used to get water to the sprinkler heads. It is important to note that insurers, and those who want added reliability, prefer two pumps to ensure a sprinkler system never fails.
Popular sprinkler system arrangements
A single water tank and two pumps are most commonly used for fire-fighting sprinkler systems. Each of the pumps has the capability to deliver water to all the sprinkler heads, should one fail. This means the system will remain fully operational at all times.
Because reliability is so important, those who require added peace of mind often opt for a water storage tank that can be split into two. These half-capacity or sectional tanks offer greater protection because the sprinkler system will remain fully operational – even during the annual inspection process, routine maintenance and repairs.
Water storage tanks used for sprinkler systems must be constructed to the highest standards. As well as being robust, they should need little maintenance, be resistant to corrosion and meet rigorous test standards set out in LPS1276.
Types of water tanks used for sprinkler systems include:
- One-piece GRP
- Half-capacity tanks
- Large, sectional sprinkler tanks
Sprinkler tanks are commonly constructed from:
- Glass coated steel
- Galvanised steel
- Epoxy coated steel
- Stainless steel
Water tanks for sprinkler systems should only ever be installed and inspected by fully trained experts. Because of the vital role they play, sprinkler tanks should be inspected at least annually and any recommendations acted upon. Written inspection reports, should also be accompanied by photographs. It is worth remembering that modern inspection techniques include underwater camera equipment which negates the need for a tank to be drained.